Twitter launched in 2006 and took several years to take off. Finally, the website began trying to monetize its wildly popular site in a big way last year with the flailing @anywhere project. More successful ad revenue projects, like promoted trending topics, allowed the micro-blogging site to rack up $45 million in revenue for 2010. Twitter's revenue number, according to eMarketer, will triple this year alone to $150 million.

Debra Aho Williamson, principal analyst for eMarketer, says that the only way for Twitter to gain the increase in revenue is "[i]f Twitter can grow its user base and convince marketers of its value as a go-to secondary player to Facebook." Lucky for Twitter, playing second to Facebook may not be all that hard to accomplish. Last August, Twitter outgrew MySpace in unique visitors and, eMarketer suggests, it will once again trump MySpace. In 2012, it will outgrow the News Corp. site in ad dollars. Increasing Twitter's user base, on the other hand, may prove something different entirely; the site currently has about 175 million registered users and studies found that 8% of people on the Internet have a Twitter account.

With a self-serve advertising platform, much like Facebook's that geo-targets users for advertisements, expected to launch this year eMarketer sees an influx in revenue up to the aforementioned $150 million in 2011 and up to $250 million in 2012. Most of the ad dollars will come from the United States, $140 million in 2011 and $225 million in 2012.

The study did not suggest if and when Twitter would become profitable.Image credit: eMarketer